In automatic transmission systems of motor vehicles and similar machines, transmission fluid is stored, delivered, transferred or processed through rigid enclosed passages, chambers, orifices, mechanisms, or pumping/metering devices, all of which require regular internal cleaning to ensure proper service and system life. Such cleansing also enhances cost effective operation because fluid contaminants, deposits of additives or by-products of the automatic power transmission process, can foul and cause premature wear to system components, or otherwise inhibit the performance and delivery characteristics of the system.
If contaminants, such as dirt, oil sludge, gum, varnish, burned oil, deposits of worn out parts, residues of transmission additives, etc., are not properly flushed out of the automatic transmission system, they are likely to cause:
Slow and hesitant acceleration PA1 Rough, skipping, slow, erratic shifting, incorrect shifting points, excessive creep and abnormal vibration while shifting gears automatically PA1 Gear position slippage or lock-up PA1 Premature transmission fluid burn-out causing excessive fluid consumption and overheating PA1 Premature transmission component wear causing rapid deterioration of system performance, as well as other symptoms.
If the above problems are not resolved in a timely manner, an expensive transmission overhaul is likely to be required.
The industry is well aware of the problems and difficulties encountered in servicing automatic transmission systems. The most common method for avoiding these problems is to change transmission fluid periodically. However, due to the design of most current automatic transmission systems, a typical fluid change replaces only from about 25% to slightly more than 55% of the used fluid.
The traditional method of changing automatic transmission fluid is to remove the dirty fluid in the pan by manually opening the pan or by withdrawing the fluid using a suction tube inserted through the dipstick tube, followed by filling the pan with fresh transmission fluid. When the pan is removed, it is also necessary to replace the gaskets, replace the filter and reinstall the pan. These servicing methods leave about 45% to 75% of the contaminated or burned fluid inside the cavities and components of the transmission system For example, the torque converter, valve body, clutch chambers, passages, etc., all retain a large amount of used automatic transmission fluid, even after such a fluid change.
To replace all of the used transmission fluid, the only other option has heretofore been a complete automatic transmission system overhaul. However, this drastic and costly method is obviously not preferred for normal transmission service.
Other proposed solutions to automatic transmission system servicing problems are in common practice today. These include the use of aftermarket transmission fluid additives between fluid changes. Such additives generally improve the physical or chemical properties of the transmission fluid. For example, they can increase viscosity, improve heat transfer characteristics, and inhibit oxidation of internal components.
Also practiced is the addition of an aftermarket transmission system detergent solvent just before each fluid change. The mixture of detergent solvent and used transmission fluid circulates within the system to dissolve and dislodge contaminants while the transmission system operates under normal conditions, i.e. with the engine turned on. After this "cleaning operation" is completed, the traditional draining method is applied to remove the mixture of used transmission fluid and detergent solvent. However, as mentioned before, only 25% to 55% of the fluid mixture is actually removed in this way.
From the above discussion, we have concluded that traditional methods of changing fluid in automatic transmission systems leave considerable amounts of used transmission fluid behind. Since it is almost impossible to completely replace the used transmission fluid without disassembling the transmission system, regular flushing of automatic transmissions is seldom carried out. Therefore, vehicle and equipment owners have not been able to obtain a completely clean automatic transmission system. In fact, traditional methods of servicing automatic transmission systems only prolongs the inevitable--failure of the automatic transmission system due to contamination of the transmission fluid. In the absence of an improved alternative service method, deterioration and early failure of automatic transmissions is expected and tolerated. If a vehicle owner tries to rectify the situation by adding aftermarket additives or using detergent solvent, damage is likely to be even more severe in the long run. In addition to the large amount of used fluid left in the transmission, detergent solvents or expired additives remain inside the automatic transmission system. These solvents or additives are generally not beneficial if allowed to remain in the automatic transmission system. They can lead to unpredictable results and side effects on various system components. Moreover, if different additives or detergent solvents are used, unwanted chemical reactions can occur between them.
In view of the foregoing, there has long been a need for a simple, effective, and inexpensive method and system capable of removing all of the used automatic transmission fluid and embedded contaminants from the internal passages and chambers of an automatic transmission system without complete disassembly of the system.
The fuel systems of internal combustion engines, where fuel is stored, delivered, transferred or processed through rigid enclosed passages, chambers, orifices, mechanisms, or pumping/metering devices, also require regular internal cleaning to ensure proper service and system life and to assure cost effective operation. If cleaning is not performed, fuel contaminants, deposits of additives, or by-products of the combustion process can foul and cause premature wear to system components, or otherwise inhibit the performance and delivery characteristics of the system.
Moreover, the significance of flushing the fuel system of the internal combustion engine without disassembly of the fuel system is a well known subject, as discussed in the following U.S. Pat. Nos.:
U.S. Pat. No. 4,197,140 Swan PA0 U.S. Pat. No. 4,520,773 Koslow PA0 U.S. Pat. No. 4,606,311 Reyes et al. PA0 U.S. Pat. No. 4,671,230 Turnipseed PA0 U.S. Pat. No. 4,787,348 Taylor PA0 U.S. Pat. No. 4,877,043 Carmichael PA0 U.S. Pat. No. 4,989,561 Hien et al. PA0 U.S. Pat. No. 5,097,806 Vataru et al. PA0 U.S. Pat. No. 4,127,160 Joffe PA0 U.S. Pat. No. 4,520,773 Koslow PA0 U.S. Pat. No. 4,606,311 Reyes et al. PA0 U.S. Pat. No. 4,787,348 Taylor PA0 U.S. Pat. No. 4,877,043 Carmichael PA0 U.S. Pat. No. 4,989,561 Hein et al. PA0 U.S. Pat. No. 5,097,806 Vatarau et al.
Therefore, in addition to the current need for an automatic transmission cleaning and draining apparatus, it is also desirable to provide the additional benefits of flushing the fuel system of an internal combustion engine without troublesome field modification.